[PATCH 06/17] i2c: omap: improve 1p153 errata handling

Felipe Balbi
2012-06-14T10:20:39Z

Make it not depend on ISR's local variables
in order to make it easier to re-factor the
transmit data loop.

Signed-off-by: Felipe Balbi <balbi-l0cyMroinI0@public.gmane.org>
---
drivers/i2c/busses/i2c-omap.c | 47 +++++++++++++++++++++++++++++------------
1 file changed, 34 insertions(+), 13 deletions(-)

diff --git a/drivers/i2c/busses/i2c-omap.c b/drivers/i2c/busses/i2c-omap.c
index 0661ca1..52861c2 100644
--- a/drivers/i2c/busses/i2c-omap.c
+++ b/drivers/i2c/busses/i2c-omap.c
@@ -768,21 +768,24 @@ omap_i2c_omap1_isr(int this_irq, void *dev_id)
* data to DATA_REG. Otherwise some data bytes can be lost while transferring
* them from the memory to the I2C interface.
*/
-static int errata_omap3_1p153(struct omap_i2c_dev *dev, u16 *stat, int *err)
+static int errata_omap3_1p153(struct omap_i2c_dev *dev)
{
- unsigned long timeout = 10000;
+ unsigned long timeout = 10000;
+ u16 stat;

- while (--timeout && !(*stat & OMAP_I2C_STAT_XUDF)) {
- if (*stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
+ do {
+ stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
+ if (stat & OMAP_I2C_STAT_XUDF)
+ break;
+
+ if (stat & (OMAP_I2C_STAT_NACK | OMAP_I2C_STAT_AL)) {
omap_i2c_ack_stat(dev, (OMAP_I2C_STAT_XRDY |
OMAP_I2C_STAT_XDR));
- *err |= OMAP_I2C_STAT_XUDF;
return -ETIMEDOUT;
}

cpu_relax();
- *stat = omap_i2c_read_reg(dev, OMAP_I2C_STAT_REG);
- }
+ } while (--timeout);

if (!timeout) {
dev_err(dev->dev, "timeout waiting on XUDF bit\n");
@@ -946,9 +949,18 @@ complete:
}
}

- if ((dev->errata & I2C_OMAP3_1P153) &&
- errata_omap3_1p153(dev, &stat, &err))
- goto complete;
+ if (dev->errata & I2C_OMAP3_1P153) {
+ int ret;
+
+ ret = errata_omap3_1p153(dev);
+ stat = omap_i2c_read_reg(dev,
+ OMAP_I2C_STAT_REG);
+
+ if (ret < 0) {
+ err |= OMAP_I2C_STAT_XUDF;
+ goto complete;
+ }
+ }

omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
}
@@ -986,9 +998,18 @@ complete:
}
}

- if ((dev->errata & I2C_OMAP3_1P153) &&
- errata_omap3_1p153(dev, &stat, &err))
- goto complete;
+ if (dev->errata & I2C_OMAP3_1P153) {
+ int ret;
+
+ ret = errata_omap3_1p153(dev);
+ stat = omap_i2c_read_reg(dev,
+ OMAP_I2C_STAT_REG);
+
+ if (ret < 0) {
+ err |= OMAP_I2C_STAT_XUDF;
+ goto complete;
+ }
+ }

omap_i2c_write_reg(dev, OMAP_I2C_DATA_REG, w);
}
--
1.7.10.4